A communication system is a facility which enables communication between two or more entities such as user terminal equipment and/or network entities and other nodes associated with a communication system. The communication may comprise for example, communication of voice, electronic mail (email), text messages, data, multimedia and so on. The communication may be provided by a fixed line and/or wireless communication interfaces. A feature of wireless communication systems is that they provide mobility for the users thereof.
An example of a communications system providing wireless communication is a public land mobile network (PLMN). An example of the fixed line system is a public switched telephone network (PSTN).
The communications system typically operates in accordance with a given standard or specification which sets out what the various elements of the system are permitted to do and how that should be achieved. For example, the standard of specification may define if the user, or more precisely user equipment is provided with a circuit switched server or a packet switched server or both. Communication protocols and/or parameters which should be used for the connection are also typically defined. For example the manner in which communications are implemented between the user equipment and the elements of the communication networks is typically based on the predefined communication protocol. In other words, a specific set of “rules” on which the communication can be based needs to be defined to enable the user equipment to communicate via the communication systems.
Various different standards have been proposed or are being proposed for telecommunication networks. Examples of such proposals are the so called third generation (3G) communication systems such as UMTS (Universal Mobile Telecommunications System). This may use CDMA (Code Division Multiple Access). This means that the wireless communications between the user equipment and a node uses a spreading code to distinguish communications. GSM (Global System for Mobile communications) is another known standard which uses a time division multiple access method for communication between user equipment and a network node.
In the currently proposed UMTS third generation system there is a cell update message which is sent by the user equipment to the radio access network. This message will indicate possible causes for the cell update. There are predefined causes which can be indicated. One of these causes is that there is “uplink data transmission”. This value is intended to cover both the need for user data transmission and control data transmission from the user equipment to the radio access network.
With the current proposal, the radio network controller (RNC) is not able to perform different procedures for these two different cases of uplink data transmission. This is because required information as to which case of uplink data transmission is the cause of the cell update is missing. Typically, the transmission of control data can be performed in the CELL_FACH (forward access channel) stage and the transmission of user data, when there is a large enough amount of data, is transmitted in the CELL_DCH dedicated channel state. The radio network controller is not able to perform state transition and non real time NRT DCH allocation directly based on the cell up date message. This is because the results of the traffic volume measurements are not available. Thus, the radio access network does not know based on this cell up date message whether the user equipment is going to perform for example an AMR (adaptive multi rate) call.
With the current proposal, the signalling can be summarised as follows:
The user equipment sends a cell update message to the radio network controller which sends a confirmation message back to the user equipment. The user equipment then sends a radio access network mobility information confirmation message to the RNC which replies with a measurement control message. The user equipment provides a measurement report to the RNC. The RNC makes a packet scheduling decision and allocated dedicated channel resources if required. The radio bearer is then reconfigured.
This has the disadvantage in that there is a lot of signalling required which is both time consuming and uses radio resource.